/*
 * Copyright (c) 2017-present, CV4J Contributors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.cv4j.core.filters;

import com.cv4j.core.datamodel.ColorProcessor;
import com.cv4j.core.datamodel.ImageProcessor;

import java.util.ArrayList;
import java.util.List;
import java.util.Optional;

/**
 * 复合过滤器
 * 组合使用多个滤镜
 *
 * @author dev
 * @date 2021/07/22
 */
public class CompositeFilters {
    private List<CommonFilter> lists;

    /**
     * 复合过滤器
     */
    public CompositeFilters() {
        lists = new ArrayList<>();
    }

    /**
     * 添加过滤器
     *
     * @param filter 过滤器
     * @return {@link CompositeFilters}
     */
    public CompositeFilters addFilter(CommonFilter filter) {
        lists.add(filter);
        return this;
    }

    /**
     * 过滤器
     *
     * @param imageData 图像数据
     * @return {@link ImageProcessor}
     */
    public Optional<ImageProcessor> filter(ImageProcessor imageData) {
        if (!(imageData instanceof ColorProcessor)) {
            return Optional.ofNullable(imageData);
        }
        if (lists != null && lists.size() > 0) {
            return filter(imageData, lists.size());
        }
        return Optional.ofNullable(imageData);
    }

    /**
     * 过滤器
     *
     * @param imageData 图像数据
     * @param size 大小
     * @return {@link ImageProcessor}
     */
    private Optional<ImageProcessor> filter(ImageProcessor imageData, int size) {
        ImageProcessor temp = imageData;
        int newSize = size;
        if (newSize == 1) {
            CommonFilter filter = lists.get(0);
            return filter.filter(temp);
        }
        newSize = size - 1;
        CommonFilter filter = lists.get(newSize);
        temp = filter.filter(temp).get();
        return filter(temp, newSize);
    }
}
